The aim of this integrated Program is to develop and assay a novel broad-spectrum combination microbicide, ZCM. ZCM comprises Zn bound to carrageenan and the non-nucleotide reverse transcriptase inhibitor MIV-150. We rationalize that preventing pathogen attachment to target cells via carrageenan, combined with the anti-HIV/STI effects of Zn and MIV150, will render this combined formulation highly effective at limiting HIV infection and STIs. Project 1 (Maguire, Project Leader {PL}) focuses on optimizing the development and testing of ZCM formulations, to identify the strongest, most stable and safe ZCM for the studies proposed in Projects 2 and 3. Experiments will involve assaying;formulations containing different concentrations of the 3 components. Stability will be assessed by standard physical and chemical methods. In vitro and FDA-required animal assays will be employed to assay toxicity and animal systems will be used for preliminary pharmacokinetic studies. The major goal of Project 2 (Pope, PL) is to test ZCM for its ability to prevent vaginal infection with immunodeficiency viruses in healthy and HSV-2-infected macaques. Since dendritic cells (DCs) likely drive the early amplification of virus in the tissues and this may be exacerbated by pathogens like HSV-2, DC-based in vitro studies will be performed in parallel to the in vivo work. We will monitor how effective ZCM is at preventing DC-driven infections, while uncovering information about the ability of ZCM to trigger innate immunity that together would contribute to the microbicide actions in vivo. Proposal 3 (Phillips, PL) involves assaying ZCM for effectiveness in preventing infection of primary isolates of HIV in primary human mononuclear cells. In addition, work will focus on developing systems for assaying microbicides against hepatitis B virus (HBV), HSV-2, Chlamydia, and Trichomonas, important STIs that have been relatively understudied by the microbicide community. ZCM will be tested in these new and improved systems for (in vitro and in vivo) efficacy in blocking these important STIs. The ultimate goal of this integrated multi-project pre-clinical study is to develop a new generation carrageenan-based microbicide, ZCM, which will be highly effective against all clinical isolates of HIV and have robust activity in preventing infection by a broad spectrum of STIs.